With over 25 million .com domains registered with Google alone, this top-level domain is by far the most popular choice worldwide. According to the domain marketplace Sedo, the average sales price for a .com domain name during the second quarter of 2015 was 4,701 dollars. The most expensive publicly traded domain names have been known to fetch eight-figures. But don’t quit your day job just yet: such sales are the exception rather than the rule.

Thanks for this post. I do good with Adsense and wanted to branch out so I bought 5 domains from Namejet after reading this thread. After the 5 auctions ended I spent $500 total. I contacted 30 people about these domains and after a few bites I was able to sell one of them for $500 so I got my money back and now what I sell the other four for is all profit. The best part about this is that it is not very time consuming. I spent maybe an hour on Namejet. I spent maybe two hours sending out emails. Thanks again!

Most popular auctions with expiring domains are at godaddy, namejet, snapnames. Search for expired domains name its very easy if you have domains list. With a bit luck, you can drop good one with PR5 cheaper like $200, just need to know which domain have not fake pr. List of domains are not free, but updated dailly with aprox. 50.000 new expiring domain names.
As far as flipping domains for a profit is concerned, there are certain domain names that are worth a lot of money. For instance, Hotel.com and Business.com have been reportedly sold for $11 million and $7 million respectively. Now even though coming across such golden domain names seems more like a long shot, you can still make a decent amount of money if you choose to buy and sell domains as a part-time business opportunity.
The second option requires a bit more time and effort than a 301 redirect. You could do a mini overhaul of the site and turn it into a microsite for your main domain. This option is good for exact-match domains for your targeted keyword, and there are other reasons for going the microsite route that Rand's highlighted in his post about root domains, subdomains, subfolders and microsites. This strategy also works better if the old domain has decent rankings for the keywords you're targeting.
Get appraisals for your domain names. When selling, you will want to know what kind of price you should expect to get for your sites. There are a variety of websites that offer free appraisals for valuation. This includes larger domain auction sites such as Sedo.com, GoDaddy.com, and DomainIndex.com. These of course are only estimates, but they can give you a good idea of what certain domains might be worth.
If you buy a dropped domain from Snap or Namejet, the backlinks seem to be worthless for SEO.  They are valuable for traffic if it's targeted to your site.  Go ahead and 301 redirect into your site because it's the traffic from the back links that is worth something.  I use the Google URL builder to redirect these names so you can see the domain the traffic is coming from.
HostGator often offers promotions, coupons and special offers to customers during their initial term. Please note that special offers are limited-time promotional prices that are available to new customers and are valid for the Initial Term only, and not for successive or renewal periods. Promotional rates apply to GATOR, Shared, Cloud, VPS, Dedicated, WordPress and Reseller hosting plans and will automatically renew after initial term at regular rate found in your control panel. Note: If you register a free domain through us and wish to cancel your account, there is a fee to retain your domain.
If you buy a domain from a 3rd party, the backlinks are valuable.  I always wait a few months before redirecting, so just set up a quick minisite until two page rank updates have passed and then go ahead and 301 redirect.  However, it seems that you'll get the link juice from the back links, the anchor text is ignored by Google.   Buying a domain at Godaddy TDName expired auctions, seem to not count as a dropped domain if you immediately set up a mini-site.

There are several types of domain names to avoid. One is intentional misspellings, as these make it less likely someone will search for them. You also want to avoid names with extra symbols like hyphens, or with added prefixes and suffixes like "e" or "my." Outside of a few notable exceptions with very strong brands (like eBay), those additions can only hurt the value.[3]
Acquiring what you believe may be a valuable domain name is the easiest part of the equation.  Finding the right  buyer is much more difficult. Using auction sites and forums is perhaps the best way to find qualified buyers that are interested in your domain, and using auctions will take some of the stress away from establishing the value of a domain name yourself.
When I first started online, I'd register domains that I thought I could develop and sell at a later time. After learning my way around the cloud, I realized many of the domains I'd registered are pretty much useless, or so I thought, and I let them expire. Come to find out several of these domains have been picked up by parking sites and are being offered for sale for thousands of dollars! Now I'm not saying they're actually selling for the asking price, but I learned my lesson. I never allow a domain name to expire. I add content to it, backlinks, some AdSense and try to sell it for something.

Here's an old post on search engine roundtable that claims google's policy is to discount previous backlink juice when a domain changes ownership.  I'm not convinced whether this is actually true or something Google says to discourage excessive domain buying / 301 redirecting for SEO benefit.  The comments above seem to give varying opinions on this matter. Would be great to get to the bottom of that one!
Park the domain with a domain parking service. Since you may not have content to put on the site, a parking service puts up a dummy page with ads. When people visit and click on the ads, that's money for you. This method works best with popular keyword domains that get lots of traffic. In most cases, you will not have control over what ads appear on your domains.[5]
Do you want to learn how to make money buying and flipping domain names? If so, this guide will provide you with the basic knowledge and direction required to get started! Unlike domain name investing, where a "buy and hold" strategy is the standard technique, domain name flipping is all about finding valuable domains and quickly selling them for a profit.
Check DA/PA: The “Domain Authority” and “Page Authority” metrics gained significant popularity over the last few years. They seem to correlate well with a domain’s ability to rank in the search engines and hence, a domain having a high DA/PA will typically have a higher value. This is not to say domains with low DA/PA can’t sell for a lot of money because, at the end of the day, it’s just one factor. However, it’s good to take a look at these as they may tip the scale in favor of or against some buying decisions.
Also, Sedo.com, makes millions a week selling domains,even in the past week[3]! If you want to sell here, I would probably use a paid category or featured listings, one of my category listings, got 44 views in just 1 week but still waiting for a sale this month, hopefully. I would not really on this as a business, unless you add web development to it, and also, be sure to check that you are making a good profit, say within 6 months!
Domains are more than a web address. They often have value that extends well beyond their initial registration price. Depending on how memorable it is or how well it ranks on Google, a domain that initially cost a few bucks can be worth a lot of money to the right buyer. That’s why domain auctions exist – to give domain owners an opportunity to sell their name for a profit, and give buyers a chance to get a name that can take their website to the next level.

When you are selling a domain name, you don’t want to suffer because of failed transactions or being tricked by defaulters. Safeguard your monetary dealings; the best way to do this is to take the help of a secure domain transfer and escrow service. The escrow system is highly beneficial because a buyer has to deposit money at the trusted source prior to purchase, and the dealing between a buyer and a seller takes place through a secure domain transfer and escrow service. This makes the transaction safer for both parties with the involvement of a neutral third party.

2) prerelease auctions.  These are domains where the auction venue has contracted with the registrar, like Fabulous or Moniker, to auction off non-renewed domains.  Just before a domain enters the pending delete process, it goes to a private auction to any person who has backordered the name.  Some people feel that back links on these type of auctions still provide a SEO benifit. My testing indicates that there is zero SEO benifit when these domains are redirected into another site.  So if you get a domain with "pink squirels" in a lot of achor text to a domain and then point it at your domain, you don't rank for "pink squirels"
Think of ways that the domains you buy would be a valuable asset to the buyer. Picture someone who would benefit from buying the domain in a space you are very familiar with. If this was you and someone was trying to sell you this name, would it be beneficial for you to own? Be honest. If so, why? If not, why? Use those answers to refine your search for names.
In the past, expired domains were used as part of black hat SEO in order to generate backlink sources quickly and easily, and this practice is still used somewhat today. Getting links in this way is not a recommendable practice. All relevant search engines work nowadays with highly complex ranking algorithms, which can no longer be outsmarted by these link networks.
So how do you develop that instinct? NameBio maintains a database of over 500,000 historical domain sales (as of writing this post). They have interesting filtering features by which you can narrow down domains by price range, date sold, keywords and more. Simply sifting through the listings on NameBio long enough will quickly develop your domain appraisal “instinct”.